This girl was in the market for a man she could exploit long before she met you. Young women don't normally send nude pics of themselves to male friends. She sent them to you because she figures you're lonely and that you will hang on in the hope that something intimate will develop between you. She read you right, didn't she?

She is not a nice person. You two are not 99% compatible. You should cut her off not because "it's the right thing to do." Cut her off because she is wasting your time. All she offers you is frustration and, eventually, real pain.

At age 20, she figures she's got lots of time to play head games with men. At age 38, you can't afford to waste your time on women who use you. Learn to move on quickly, when a woman is not a good catch. Move on and keep dating new women. That way you maximize your odds of finding someone decent.